In a gas turbine engine, air is pressurized in a compressor, mixed with fuel in a combustor, and ignited for generating hot combustion gases. The hot combustion gases flow downstream through several turbine stages so as to extract energy therefrom. The pressurized air from the compressor may surround the combustor so as to cool the liners thereof. The pressurized air also may be extracted so as to cool the various turbine stages.
The compressor thus has several pressurized cavities such as extraction cavities in communication with the turbine and otherwise. For example, known double wall casing configurations for a compressor with extraction cavities may have a floating member that may move in radial and axial directions so as to accommodate thermal growth. Such movement, however, may make sealing between the extraction cavities difficult. Moreover, quantifying the leakage through the cavity interfaces also may be difficult to determine.
There is thus a desire for improved seals and sealing methods for the interface between a high pressure extraction cavity and a lower pressure extraction cavity. Such improved seals and methods may increase compressor performance as well as overall system performance and efficiency.